A smart card or integrated circuit card (ICC) is a device with the dimensions of a credit card for the safe storage of data. In particular, the integrated circuit card includes a plastic substrate which has, embedded in it, a microchip (i.e., the integrated circuit) which stores the data and provides calculation functions. The plastic substrate has a standard size and form, which is generally indicated by the term “form factor” (abbreviated FF) and a number which identifies the different formats of the cards.
Originally, the size of the integrated circuit cards was that of a credit card (Full-size Smart Card, 1FF—85.60 mm×53.98 mm×0.76 mm). Following the development of mobile devices, which are physically becoming increasingly smaller, the cards have undergone a miniaturization and re-dimensioning process. Over the years this has resulted in a reduction in the amount of the plastic substrate surrounding the integrated circuit.
The most common formats are essentially three in number and differ from each other only in terms of dimensions (length×width×depth).
Mini-SIM (2FF) 25 mm×15 mm×0.76 mm
Micro-SIM (3FF) 15 mm×12 mm×0.76 mm
Nano-SIM (4FF) 12.30 mm×8.80 mm×0.67 mm
Essentially, the integrated circuit in a particular sector of the 1FF format card forms a small-size card which may be used for specific applications. For example, in the 2FF format (ISO/IEC specification 7810:2003), the card may be used with most cellular phones. In the 3FF format (ETSI TS 102 221 V9.0.0 specification) it may be used with certain smart phones, such as the iPhone 4. In the 4FF format (ETSI TS 102 221 V11.0.0 specification) it may be used in the most recent iPhone 5.
The various formats 2FF, 3FF and 4FF are usually integrated within the substrate with a full-size or 1FF format and, by a system of pre-cuts, they may be removed from it so as to allow the end user to remove and use the format suitable for the particular receiving slot in his/her device.
Although initially such a system for incorporating several formats was considered to be an instrument useful and advantageous for the client, a technical problem was subsequently encountered, resulting in the need to reconsider the validity of the current approaches.
More specifically, this problem relates to the fact that it has become an increasingly established practice to use the various disposable frame-pieces of the various formats as an “all purpose” approach for the related card. This occurs in particular when, for example, the format 2FF is used as an adapter for the 3FF format or the format 3FF is used as an adapter for the 4FF format.
The main drawback of this practice has been identified by the manufacturers of mobile devices who, following the use of the disposable frame-pieces as adapters for a smaller format, have noted that there is a substantial deterioration of the contact slides inside the slots which are designed to receive the SIM card.